Hello,
I have this problem,
In my new project with max2013 i import a scene from revit fbx with link manager,
than I replace the Autodesk materials with the vray material.
if I change the Revit scene, I must re-export the fbx and reimport it
In The new scene with modified object 3dsmax assigns new materials duplicates even if I flag the 2 options
Ex.
Material 1 ---- vray materia
Material 1 ---- autodesk material
3dsmax file
https://docs.google.com/open?id=0B-TvsU5ZUuuBd1BvUjBjLTJ1alk